A week after Shinzo Abe's controversial visit to the Yasukuni Shrine on the first anniversary of his return to power as Japan's prime minister, the motivations behind the inflammatory gesture remain puzzling. But whatever his aim, the repercussions will further complicate the handling of several thorny regional issues. In a region already bedevilled by maritime tensions and an increasingly unpredictable North Korea, experts said Abe's visit to the shrine on December 26 had shut down avenues for dialogue on how to better manage these issues. And this poses a dilemma for Japan's biggest ally, the United States. "It's a weird kind of political dynamic in East Asia now," said David Arase, a professor of international politics at the Johns Hopkins University-Nanjing University Centre. Abe's shrine visit represents a reversal of his first-term policy, and its timing caught many by surprise. When he succeeded Junichiro Koizumi in 2006, Abe steered clear of the shrine and made a priority of repairing relations with China and South Korea. Japan's ties with both were strained under Koizumi, whose repeated visits to the shrine were seen an affront, given that 14 "class A" war criminals are among the millions of war dead enshrined there. Watch: Abe's controversial visito to Yasukuni Shrine But after regaining power in 2012, Abe made it clear that he regretted not visiting the shrine during his first stint as prime minister. Some quietly expected a shrine visit by Abe, but few thought it would take place on the first anniversary of his second term. To Japan's neighbours, Abe is sending a strong message that he is no longer interested in mending ties with them, said Michael Auslin, director of Japanese studies at the American Enterprise Institute in Washington. "Abe tried, in his own interpretation, for a year to get better relations with both countries, and at the end of that first year relations were worse … going to the shrine was a way to send the message to Beijing and Seoul that he understands that they do not want better relations, and he is fine with that," said Auslin. But regional diplomacy is more complicated than it was during Koizimi's time, and Abe could face broader consequences. The possibility of managing maritime risks in the East China Sea has been considerably diminished, said Sheila Smith, a senior fellow of Japan Studies at the Council on Foreign Relations. "So now risk reduction [on the East China Sea] is not possible as there is no diplomatic dialogue, and now with more hardening of positions between the two countries, this means we are in for a very intense couple of years in the East China Sea," Smith said. With Sino-Japanese tensions over a set of uninhabited islands flaring up in recent years, and civilian and naval patrol boats converging on the area, there were already concerns about the potential for conflict. Tension escalated in November when China declared an air defence identification zone above the sea. Complicating calculations is the potential for instability in North Korea. The recent execution of Jang Song-thaek, the once-powerful uncle of North Korean leader Kim Jong-un, has raised concerns that Pyongyang could make a provocative gesture of its own. China lost an important conduit of communication with Pyongyang in Jang, and co-ordination between Seoul and Tokyo is likely to be absent. For Washington, the shrine visit, which the US described as a "disappointment", presents a dilemma. Analysts said Washington was frustrated not only because Abe had escalated tensions but because he made repairing ties between Seoul and Tokyo almost impossible. This impedes US President Barack Obama's "Asia Pivot" policy. "For the US, it's very difficult that two major allies are not talking to each other. It hurts planning and hurts your influence," said Auslin. As Japan finalises debate on a reinterpretation of its constitution this year, Abe could finally be able to push through his vision of greater overseas presence for Japan's self-defence force. If adopted, the reinterpretation could allow Japan to provide military support to the US and its allies outside Japan's territory. "This is increasingly important for both Japan and US," said Arase. "The US is starting to have its hands full in the event of China's military build-up. The US never needed help to deal with the Soviet Union and China in the past - now it might." Abe's shrine visit was quickly followed by an agreement to relocate a US military base away from populated areas in Okinawa, Japan, a deal long sought by Washington. The timing suggested a calculated move by Abe, Auslin said. "He knew the shrine visit was going to cause Washington heartburn, but he was offsetting it with stuff that is objectively more important."